Re: Unltd data transfer of responsibility

Yes.

When a line gets transfered from one account to another account, or transfered from one person's name into another, then all grandfathered features are removed and you're required to choose from the current plans that AT&T offers.

For example, John Smith has 5 lines, all of which have unlimited data plans. His daughter wants to take her number and move it into her friend's account.

John's daughter will loose her grandfathered plan / unlimited data plan when/if she transfers her service from John's account to her friends.